By Marice Richter FORT WORTH, Texas, Feb 12 (Reuters) - The first person in the United States to be exonerated posthumously on the basis of DNA evidence received a lasting tribute in his home state of Texas this week. State officials and the family of the late Tim Cole unveiled the first Texas historical marker dedicated to an exonerated convict, located in a Fort Worth cemetery a few feet from the grave where Cole was buried in 1999. Governor Rick Perry issued Texas' first posthumous pardon to Cole in 2010, over a decade after he died from complications from an asthma attack while serving time in prison for a rape he did not commit. "We finally have something visual that people can see to remember Tim," Cory Session, Cole's brother, told Reuters. "We are very pleased and grateful that Tim's life and legacy will not be forgotten." Post-conviction DNA testing has exonerated nearly 290 people in the United States since 1989, including 17 death row inmates, according the Innocence Project, which works to reverse wrongful convictions. It says that witness misidentification was a factor in nearly 75 percent of cases. Of the DNA exonerations nationwide, over 40 have been in Texas, more than in any other U.S. state. The Texas marker tells the story of how Cole was convicted in 1986 of raping a fellow student at Texas Tech University and was sentenced to 25 years in prison. An Army veteran, Cole served more than 13 years in prison, steadfastly insisting he did not commit the crime. He turned down a plea bargain before his trial and a parole opportunity because he refused to admit guilt. His family's continued efforts to clear his name were boosted by the Innocence Project of Texas, which received a letter in 2007 from an inmate confessing to the crime that Cole was convicted of committing. Preserved DNA evidence confirmed that Jerry Wayne Johnson - not Cole - committed the rape. The victim of the attack, Michele Mallin, had identified Cole as her attacker in a photo and physical lineup but later joined efforts to bring him justice, said Gary Udashen, president of the Innocence Project of Texas. The legal maneuvers to clear Cole's name were successful, and in 2009 he was cleared in court of the crime "to a 100 percent moral, legal and factual certainty," the marker reads. "Tim Cole's case is extremely significant and has made a real difference in the bringing justice to those falsely convicted in Texas," Udashen said. The case prompted passage of two laws, including the Tim Cole Compensation Act, passed by the Texas Legislature in 2009, which provides compensation to those wrongly imprisoned. The legislature also created the Timothy Cole Advisory Panel on Wrongful Convictions to help prevent future such convictions in Texas. The marker was the result of a two-year effort by Cole's family. "I was driving my daughter through another cemetery to visit a grave when we saw a historical marker," said Session, policy director for the Innocence Project. "I decided right then that's what I wanted for Tim." (Reporting By Marice Richter; Editing by Corrie MacLaggan and Cynthia Johnston)